Over the course of my first two years of research, I defined a series of design requirements for village-scale water purification in rural India, used those requirements to justify the use of photovoltaic (PV)-powered electrodialysis (ED) technology, created an analytical model for how PV-ED systems behave, and validated that model at a laboratory scale. In the first year of my PhD, I used these insights to build our first full-scale system and completed testing of that system in Alamogordo, NM. Now, in the fourth year of my PhD, I look forward to designing and testing our first three prototype plants: two in India, and one in Gaza.

Saline groundwater, which underlies 60% of India, can negatively impact health as well as cause a water source to be discarded because of its poor aesthetic quality. A quarter of India's population live in villages of 2000–5000 people, many of which do not have reliable access to electricity. Most village-scale, on-grid desalination plants use reverse osmosis (RO), which is economically unviable in off-grid locations. Within the salinity range of groundwater in India, ED requires less specific energy than RO (75% less at 1000mg/L and 30% less at 3000mg/L). At 2000 mg/L, this energetic scaling translates to a 50% lower PV power system cost for ED versus RO. PV-ED has the potential to greatly expand the reach of desalination units for rural India.

USAID Desal Prize

The goal of the Desal Prize was "to incentivize the creation of an environmentally sustainable small-scale brackish water desalination system that can provide potable water for humans, as well as water appropriate for crops in developing countries." With an application submitted in August of 2014, our MIT/Jain team became one of 68 applicants to the prize. In December 2014 our team was selected one of 8 semifinalist teams. The competition, which was on-site at the Brackish Groundwater National Research Facility in Alamogordo, New Mexico, consisted of two, 24-hour, test periods. At the end of each cycle, water samples were analyzed and the quantity of both product and waste water was measured. The teams were judged on high water recovery, meeting quality indicators, an economic analysis, and sustainable maintenance and service schemes.

Our MIT/Jain team won first place at the competition and the $140,000 prize. In addition, the team received funds to complete a pilot in Jalgaon, India in Fall 2015. The Desal Prize pushed the development timeline for our technology, asked us to question our assumptions early, and gave us the opportunity to interact with experts both from other teams and from within the group of judges. I will always be grateful for the opportunity to learn from this amazing prize competition.

Sponsors

I would like to thank the following companies, organizations, and individuals for financially sponsoring my work in desalination.